Combustor heat shields are typically cast from high temperature resistant materials. The casting process is known to be relatively expensive. Furthermore, the casting materials used for combustor heat shield applications may require pack coating for improved oxidation resistance, which adds to the manufacturing costs.
Also, such heat shields are typically produced as a one piece casting, with studs and rails in place. When effusion holes are drilled into the heat shields, special care must be taken to avoid striking the rails and other heat shield details.
Accordingly, it is desirable to have an alternate heat shield construction.